Kerrin631 Kerrin631 - 1 month ago 16
Javascript Question

How can I alter the zooming capability on a d3 sunburst chart?

I am trying to alter the traditional zooming feature on a sunburst chart. Traditionally when you click on a partition, that partition grows to cover 100% of the base layer while all other partitions on the same layer disappear. The children of the selected partition all grow to fill the newly created space.

My current code does just what I stated above. I would like to alter my code to allow for the selected partition to only take up 75% of the base layer. The children elements will grow to cover this new space but the remaining 25% will still contain all other non-selected partitions.

I have tried altering the 't' value that is returned from d3.interpolate() but I have had unpredictable results.

I hope my description is clear.

Does anyone have any thoughts on this?

<script>

var width = 960,
height = 700,
radius = Math.min(width, height) / 2;

var x = d3.scale.linear()
.range([0, 2 * Math.PI]);

var y = d3.scale.linear()
.range([0, radius]);

var color = d3.scale.category20c();

function percent(d) {
var percentage = (d.value / 956129) * 100;
return percentage.toFixed(2);
}

var tip = d3.tip()
.attr('class', 'd3-tip')
.offset([-10, 0])
.html(function(d) {
return "<strong>" + d.name + "</strong> <span style='color:red'>" + percent(d) + "%</span>";
})

var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height)
.append("g")
.attr("transform", "translate(" + width / 2 + "," + (height / 2 + 10) + ")");

svg.call(tip);

var partition = d3.layout.partition()
.value(function(d) { return d.size; });

var arc = d3.svg.arc()
.startAngle(function(d) { return Math.max(0, Math.min(2 * Math.PI, x(d.x))); })
.endAngle(function(d) { return Math.max(0, Math.min(2 * Math.PI, x(d.x + d.dx))); })
.innerRadius(function(d) { return Math.max(0, y(d.y)) })
.outerRadius(function(d) { return Math.max(0, y(d.y + d.dy)) });

d3.json("flare.json", function(error, root) {
var g = svg.selectAll("g")
.data(partition.nodes(root))
.enter().append("g");

var path = g.append("path")
.attr("d", arc)
// .attr("stroke", 'black')
// .style("fill", function(d) { return color((d.children ? d : d.parent).name); })
.style("fill", function(d, i) {
return color(i);
})
.on("click", click)
.on('mouseover', tip.show)
.on('mouseout', tip.hide);

var text = g.append("text")
.attr("transform", function(d) { return "rotate(" + computeTextRotation(d) + ")"; })
.attr("x", function(d) { return y(d.y); })
.attr("dx", "6") // margin
.attr("dy", ".35em") // vertical-align
.text(function(d) {
if (percent(d) > 1.35) {
return d.name;
}

})
.attr('font-size', function(d) {
if (d.value < 100000) {
return '10px'
} else {
return '20px';
}
})
.on("click", click)
.on('mouseover', tip.show)
.on('mouseout', tip.hide);

function click(d) {
console.log(d)
// fade out all text elements
text.transition().attr("opacity", 0);

path
.transition()
.duration(750)
.attrTween("d", arcTween(d))
.each("end", function(e, i) {
// check if the animated element's data e lies within the visible angle span given in d
if (e.x >= d.x && e.x < (d.x + d.dx)) {
// get a selection of the associated text element
var arcText = d3.select(this.parentNode).select("text");
// fade in the text element and recalculate positions
arcText.transition().duration(750)
.attr("opacity", 1)
.attr("transform", function() { return "rotate(" + computeTextRotation(e) + ")" })
.attr("x", function(d) { return y(d.y); });
}
});
}
});

d3.select(self.frameElement).style("height", height + "px");

// Interpolate the scales!
function arcTween(d) {
console.log(d.name, x.domain())
console.log(d.name, y.domain())
console.log(d.name, y.range())
var xd = d3.interpolate(x.domain(), [d.x, d.x + d.dx]),
yd = d3.interpolate(y.domain(), [d.y, 1]),
yr = d3.interpolate(y.range(), [d.y ? 20 : 0, radius]);
return function(d, i) {
return i
? function(t) { return arc(d); }
: function(t) {
console.log(t)
x.domain(xd(t));
y.domain(yd(t)).range(yr(t));
return arc(d);

};
};
}

function computeTextRotation(d) {
return (x(d.x + d.dx / 2) - Math.PI / 2) / Math.PI * 180;
}



Answer

I found the solution here: https://bl.ocks.org/mbostock/1306365. This example manages the zoom without getting rid of the sibling nodes.